High-frequency signaling system



Aprifl 22 192%. 1,491,450

- W. c; WHITE HIGH FREQUENCY SIGNALING. SYSTEM Filed Feb. 4, 1920 In\/ento1-"- William C. White His 'Attorney.

:1. systems and WILLIAM C. WHITE, OF SOHENECTAQDY, NEW YORK, ASSIGNOR T COMP, A CORPORATION OF YORK.

GENERAL ELECTRIC HIGH-FUEN CY SIGNIG SYSTEM.

Application flled- February a, 1920. Serial No. 856,835.

T 0 all 'wliomit may co werm Be it known that 1, WILLIAM C. WHITE, a citizen of the United States, residin at Schenectady, county .nf Schenectady, tate of New York, have invented certain new and useful Improvements in High-Frequency Signaling Systems, of which the fol lowing is a specification.

My present invention relates to -signaling articularly to systems for transmitting hlgh frequency signaling currents.

The object of my invention is to rovide an efiicient way for producing an transmitting high frequency signaling currents and for interrupting the production and transmission 0 such currents in accordance with signals W ihh it is desired to transmit.

In carrying out my invention I referably employ for producing the hig frequency currents an electron discharge device comprising a highly evacuated receptacle containinga cathode, an anode and acontrolling rid. It is well known that if a device of this type has associated therewith a plate or output circuit and a grid or input circuit and these circuits are properly coupled together high frequency currents will be produced in the circuits which are especially suitable for signaling purposes. It is also well known that the current in such a device may be interrupted if a sufficiently high negative potential is impressed on the grid. I, therefore, take advantage of these characteristics of such a device and provide means for impressing upon the grid a high negative potential whenever it is desired to stop the production of high frequency currents in order to modify the transmission in accordance with signals.

My invention will best be understood by reference to the following description taken in connection with the accompanying drawing in which Figs. 1 and 2 show diagrammatically two different circuit arrangements which may be used in carrying my invention into effect.

I have indicated in the drawing an electron discharge device 1 which comprises a filamentary cathode 2, an anode 3 and a.

controlling Igrid 4 enclosed in an evacuated envelope. n the form of my inventlon indicated in Fig. 1 a plate or out ut circuit which is associated with the evice 1 includes a direct current source 5 and an inductance 6, which is also a part of the circuit of antenna 7. A grid or input circuit associated with the device '1 includes an inductance 8 which is coupled to the inductance 6 of the plate circuit, a condenser 9 which is shunted by the high resistance 10 and a condenser 11 which may be short circuited by pressing the key 12. When this key is open the grid 4; will be charged to such a high negative potential that no oscillations will be produced in antenna 7. When the key 12 is pressed and condenser 11 is short circuited thereby a portion of the negative charge on the grid will leak ofi through the resistance 10 and the system will begin to produce high frequency oscillations in the antenna 7. When the key 12 is opened the grid 4 at oncetakes on a high negative charge and the groduction of 08011- lations is interrupted n this way it is possible to produce and transmit high frequency impulses correspondin to the impulses desired for the transmlssion of the telegraphic message. The resistance 10 is preferably of such a value that the grid 4 is always slightly negative or at least is ositive with respect to the cathode only or a very small portion of the high frequency cycle. As a result the current which will be carried by-the ke "12 and which must be broken when the ey is opened will always he very small. This method of signaling also permits of a much greater output with a device of a given continuous current 1 capacity than when oscillations are produced continuously because of the fact that the device carrles current only during the time when energy is being radiated from the antenna.

In the arran ement shown in Fig. 2 the same result is o tained by omitting the condenser 11 and placing the key 12 in series with the resistance 10. In this case I have shown the coil 6 in the plate circuit coupled to a coil 13 in the antenna circuit and the coil 8 in the grid circuit cou led to a coil 14 in the antenna circuit. l he grid and plate circuits are therefore coupled together through the medium of the antenna circuit.

While I have indicated only two ways in which my invention may be carried into effect, it is apparent that many other modifications in the precise manner in which the circuit connections are made and in the particular apparatus. used may be employed ioo without departing from the scope of my invention as set forth in the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States, is,

1, Signaling means comprising an electron discharge device having a cathode, an anode and a grid enclosed. in a highly evacated receptacle, a circuit connecting said cathode and anode, a source of current in said circuit, a second circuit connecting the cathode and grid, said circuits being coupled together in such a way that high frequency currents will be produced therein, a signaling device connected directly in said grid circuit and means controlled by said signaling device whereby the grid may be charged sufliciently negative by an accumulation of electrons from the cathode to prevent the production of oscillations.

2. Signaling means comprising an electron discharge device having a cathode, an anode and a grid enclosed in a highly evacuated receptacle, a circuit connecting said cathode and anode, a source of current in said circuit, a second circuit connecting the cathode and grid, said circuits being coupled together in such a way that high frequency currents will be produced therein, a condenser connected in series in said grid circuit whereby a negative potential may be produced on saidgrid of sufficient value to prevent the production of oscillations and a signaling device directly associated with said condenser in said grid circuit for short circuiting the same and permitting the pro duction of oscillations.

3. Signaling means comprising an electron discharge devicehaving a cathode, an anode and a grid enclosed in a highly evacuated receptacle, a circuit connecting said cathode and anode, a source of current in said circuit, a second circuit connecting the cathode and grid, said circuits being coupled together in such a way that high frequency currents will be produced therein, a condenser connected in series in said grid circuit whereby a negative potential may be produced on said grid of sufiicient value to prevent the production of oscillations and. a signaling device and a resistance directly associated with said condenser and connected in said grid circuit in such a wayjthat when the signaling device is operated the condenser will be shunted by the resistance and oscillations will be produced.

4. A signaling system comprising an electron discharge device having a cathode, an anode and a grid enclosed in an evacuated receptacle, grid and plate circuits associated with said device, means for supplying high frequency currents from said plate circuit to a 'utilizationcircuit, means for producing high frequency currents in said grid circuit, a condenser connected in series in said grid circuit, and a signaling device and a resistance directly associated with said condenser in said grid circuit insuch a way that when the signaling device is operated the condenser will be shunted by the resistance and high frequency currents will be supplied to the utilization circuit.

5. A signaling system comprising an electron discharge device having a cathode, an anode and a grid enclosed in anevacuated receptacle, grid and plate circuits associated with said device, means for supplying high frequency currents from said plate circuit to a utilization circuit, means for producing high frequency currents in said grid circuit, a condenser in said grid circuit and a signaling device connected directly in said rid circuit for short circuiting said condenser when it is desired to supply currents to the utilization circuit.

In witness whereof, I have hereunto set my hand this 3rd day of February, 1920.

WILLIAM C. WHITE. 

